Newbie to a Honda forum. Trying to help son out with an old 96 Civic LX with Check engine light on.

He has this code PO705 - Short in Transmission range switch circuit. Along with PO135 and PO155. Possibly a faulty A/F sensor?

Wondering what he should check or try to replace first. Or does he need to address both? I think 135 and 155 are the same fix?? Any help is appreciated. Also, any recommendation for Honda parts on-line?

Thanks!

 

P0155 is not a Honda CEL code. Double check.

Reset ECU. Do all codes return?

 

hmmm....these codes came from a Auto Zone test? I don't have a the unit to test (but learned they can be bought). Tired of mechanics telling me it could be a number of codes, say they tried this or that, then the light goes on after a day or so and I'm out $75 -100 for the test. I will look at the useful links you've provided. Much appreciated.